// 楼层和位置编码
exports.toHex = (num) => {
  var rs = "";
  var temp;
  while(num/16 > 0){
    temp = num%16;
    rs = (temp+"").replace("10","a").replace("11","b").replace("12","c").replace("13","d").replace("14","e").replace("15","f") + rs;
    num = parseInt(num/16);
  }
  //转大写
  return '3ST' + rs.toLocaleUpperCase().padStart(13,"0");
}
exports.randNum4 = () => {
  return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1)
}

